Typically, the three dimensional images are created through the user's eye by the stereo image theory. Namely, when the eyes are separated with 5-7 cm, the images caught by the two eyes are slightly distinguishable, and it leads to the result of visual difference. Thus, the traditional three-dimensional image is obtained by the visual difference effect so as to allow the left eye to only receive the left-eye image while the right eye only receives the right-eye image.
Typically, the visual difference based three-dimensional image needs a special design equipment to achieve the goal, and the typical methods are introduced as follows.
The first type introduces the polarized glasses which includes a horizontally polarized glass and a vertically polarized glass for each eye to allow the left eye to receive the horizontally polarized image and the right eye to receive the vertically polarized image. The display apparatus may radiate the horizontally polarized left-eye image and the vertically polarized right-eye image, respectively. By the method, the left eye of the user may receive the horizontally polarized left-eye image while the right eye of the user may receive the vertically polarized right-eye image, and thereby creating the three-dimensional image. However, when the head of the user slightly inclines, the light in the other orientation of polarization will be not completely filtered by the polarized glasses. It will cause the user to be uncomfortable.
The second type involves the usage of red-blue (green) glasses. The technique introduces the displaying of the left, and the right images by using the red-blue (green) glasses to allow the user to receive the left and the right images by each eye, respectively, and thereby creating the three-dimensional image after receiving the left and the right images through the red-blue (green) glasses. However, the shortcoming of the type of the three-dimensional image displaying is that the true color of the original image cannot be re-built by using the red-blue (green) glasses. The third type of the prior art involves the usage of the shutter glasses. The image displaying apparatus will transmit odd images and even images to the shutter glasses, respectively. If the odd images are set to act the right-eye images while the odd images are defined as the left-eye images, then the odd images are transmitted, and the left eye will be covered by the shutter glasses. Similarly, when the even images are transmitted, the right eye will be covered by the shutter glasses so as to allow the user to watch the three-dimensional image. The fourth type is called helmet type image display which has two liquid crystal displays on the glasses directly, and the user receives the left and the right eye images through the two displays by the left and the right eyes, respectively. This type is better than the first type and the second type. However, the cost of the manufacture is high, and the number of the users to watch the images is limited.
No matter the cost of the manufacture of those prior arts is, for all of the prior arts mentioned above, the glasses is required for the user to wear on for watching three-dimensional image. It is inconvenient to the user at all. Thus, the recent development is mainly focusing on the glasses-free three-dimensional image display apparatus.
One of the types which involves the glasses-free three-dimensional image display apparatus is called visual-difference bare-eye three-dimensional image display apparatus which is designed based on the visual difference phenomena. Under the scheme of the visual-difference bare-eye design, a parallax or an optical grating is set before the liquid crystal display. The left-eye image and the right-eye image are transmitted in sequence. The parallax functions to allow the right-eye and the left-eye to receive the right-eye and the left-eye images, respectively. The signals of the right-eye and the left-eye images will be re-constructed by the brain of the user, and thereby achieving the three-dimensional image.
In addition to the above glasses-free three-dimensional image display apparatus, a further glasses-free three-dimensional image technique involves Integral Photography (IP) technology which has developed since 1908. The major working principle of the IP is using the fly's eye lens to catch the stereo images from different angle. The fly's eye lens simulates the arrangement of the eye of the fly to arrange pluralities of tiny lens in an array configuration. Namely, pluralities of semi-sphere lens are arranged within a planar in an array for facilitating catching image. The Integral Photography (IP) technology involves two major steps, and the first one may refer to FIG. 1A, wherein an image capture device 105 catches the stereo image 107 from different angle of the object 101 by the fly's eye lens 103. Thereafter, referring to FIG. 1B, the next step is to process the captured images through the display apparatus 109 and the fly eye lens 103 to re-built the three-dimensional stereo image 110 of the object.
From above mentioned, the parallax or optical grating is required within the display apparatus as using the visual difference three-dimensional image technique. A fly's eye lens is required within the display apparatus to show the three-dimensional image as using the IP three-dimensional image technique. When the user uses specified display apparatus for display the three-dimensional image generated by specified method, the usage will be limited by the specified display apparatus. If data of the captured images is not compatible to the hardware, then the three-dimensional image cannot be displayed at all.